A PROTEIN KINASE IS REQUIRED FOR PROPER NODULATION IN THE COMMON BEAN-Rhizobium etli SYMBIOSIS

CLÚA, JOAQUIN; RIPODAS, CAROLINA; BATTAGLIA, MARINA; ZANETTI, MARIA EUGENIA; BLANCO, FLAVIO

MAR DEL PLATA

Congreso; Sociedad Argentina de Investigacion en Bioquimica y Biologia Molecular; 2015

SAIB

Phaseolus vulgaris is an agronomical important legume that establishes a nitrogen-fixing symbiosis with Rhizobiumetli. In this interaction, bacteria infect the root to reach the nodule, a post-embryonic organ formed by division ofcortical cells. A previous study from our laboratory showed that the C1 subunit of the plant nuclear factor NF-Y is akey regulator of infection and nodule organogenesis. In order to identify other factors involved in this signalingpathway, a yeast two hybrid screening was performed. One of the positives clones encodes a protein kinase with atransmembrane domain at the N-terminus. The interaction has been confirmed by both co-immunoprecipitation andbimolecular fluorescence complementation. The protein is distributed between the plasma membrane and thecytoplasm. Post-transcriptional silencing of the kinase by RNAi led to a reduction in the number and size of nodulesand affected the infection thread formation in P. vulgaris roots. Interestingly, partner selection between high- andlow- quality symbiotic partners was also affected in coinoculation experiments. Taken together, these results suggestthat this gene is required for rhizobial infection, nodule organogenesis and the molecular mechanism underlyingbacterial strain preference.